Video by Line 6 Movies via YouTube
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Paul Hindmarsh demonstrates the Harmony and Heliosphere delays in the Line 6 DL4 MkII delay pedal. Paul is playing his custom Yamaha Pacifica guitar and the DL4 MkII is routed into a pair of Princess amplifier models in a Helix Floor amp and effects processor. For the Harmony delay, the notes are repeated an octave lower, then an octave higher, then back to unison. Heliosphere is a lush stereo delay with subtle modulation and a splash of reverb on the delays only.
Learn more about DL4 Mk II: https://line6.com/effects-pedals/dl4-mkii/